US 12,106,528 B2
Generating scene flow labels for point clouds using object labels
Nichola Abdo, Mountain View, CA (US); Jonathon Shlens, San Francisco, CA (US); Zhifeng Chen, Sunnyvale, CA (US); Christopher John Sweeney, San Francisco, CA (US); and Philipp Florian Jund, Zurich (CH)
Assigned to Waymo LLC, Mountain View, CA (US)
Filed by Waymo LLC, Mountain View, CA (US)
Filed on Mar. 1, 2022, as Appl. No. 17/684,334.
Claims priority of provisional application 63/155,255, filed on Mar. 1, 2021.
Prior Publication US 2022/0319054 A1, Oct. 6, 2022
Int. Cl. G06T 9/00 (2006.01); G06F 18/214 (2023.01)
CPC G06T 9/002 (2013.01) [G06F 18/2148 (2023.01)] 20 Claims
OG exemplary drawing
 
1. A method performed by one or more computers, the method comprising:
obtaining a current point cloud representing an observed scene at a current time point, wherein the current point cloud is generated from measurements of a sensor at the current time point, and wherein the current point cloud comprises a plurality of current three-dimensional points;
obtaining object label data that identifies a first three-dimensional region in the observed scene that has been labeled as containing a first object in the observed scene at the current time point;
determining, for each current three-dimensional point that is within the first three-dimensional region and using the object label data, a respective preceding position of the current three-dimensional point at a preceding time point in a reference frame of the sensor at the current time point; and
generating a scene flow label for the current point cloud that comprises a respective ground truth motion vector for each of a plurality of the current three-dimensional points, wherein generating the scene flow label comprises:
for each of the current three-dimensional points in the first three-dimensional region, generating the respective motion vector for the current three-dimensional point from a displacement between (i) a current position of the current three-dimensional point at the current time point in the reference frame of the sensor at the current time point and (ii) the preceding position of the current three-dimensional point at the preceding time point in the reference frame of the sensor at the current time point.